The Local Mean Time

The time elapsed from the midnight of the place is  known as local mean time. Thus L M T at midnight is  zero hours. This is different from the hour-angle of the mean Sun. The Earth is rotating from the west to east and it completes one rotation with respect…

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Mean Solar Day

We have seen that the Sun appears to describe an elliptical orbit around the Earth and its rate of change of direction in the orbit is not constant, i.e. the Sun appears to move somewhat non-uniformly in the zodiac. It moves faster when the Earth is at its perihelion, i.e….

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COMBUSTION

The planets are called combust when they are near the Sun in longitudes and their rays which are the reflection of the Sun’s rays are intermingled with that of the Sun whose rays are much stronger. Therefor, the effect of the planets becomes much less. I ‘he planet under combustion…

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OCCULTATION

Moon’s sidereal period of revolution is about 277, days and it moves eastwards with reference to the  stars and at an average of more than half a degree per hour. In its movement, it continually interposes  its  disc between us and the stars. The sudden disappearance of a star by…

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SOLAR ECLIPSE

The solar eclipse will occur when the Moon is in between the Earth and the Sun i.e. (1) It will be an amavasya. (2) The Moon must be on or near Rahu or Ketu so that its latitude is near zero and the three heavenly bodies, the Moon, the Earth…

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LUNAR ECLIPSE

A lunar eclipse takes place when the Moon passes through the shadow of the Earth in the heavens. This will only occur when all the three i.e. the Sun, the Earth and the Moon are nearly in a straight line. The Sun and the Earth are always on the ecliptic…

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Eclipses

The Sun is the only illuminated heavenly body which is actually a star in the solar system and Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto are its planets, reflecting the light received from it. All the planets are revolving around the Sun as already explained in chapter…

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SYNODIC PERIOD

Synodic  period is the interval of time which   elapses  between two oppositions or two conjunctions of a superior planet. In case of inner-planets it is the time  between two conjuntions of the same type whether  they are both inferior or superior. It can be explained as under: The  Sun…

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SIDEREAL TIME

Time, includingsidereal time, can be measured in many ways. Sidereal day is the time elapsed since the precedding transit of Sayana first point of Aries to the next transit of the meridian of a place. In other words, one sidereal day is the time taken by the Earth in completing…

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SIDEREAL PERIOD

Sidereal period or periodic time of a planet is the time taken by it to make a complete revolution with reference to the fixed stars. In the case of the Moon it is 27 days 7 hours and 43 minutes. This is the minimum sidereal period among nava  grahas. The…

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